[bootlin/training-materials updates] master: Embedded Linux: explain what happens with an initramfs without /init (b56c33f7)
Michael Opdenacker
michael.opdenacker at bootlin.com
Fri Nov 12 16:42:40 CET 2021
Repository : https://github.com/bootlin/training-materials
On branch : master
Link : https://github.com/bootlin/training-materials/commit/b56c33f72de6bd12b3184135bbf06955951e6a1e
>---------------------------------------------------------------
commit b56c33f72de6bd12b3184135bbf06955951e6a1e
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date: Fri Nov 12 16:42:40 2021 +0100
Embedded Linux: explain what happens with an initramfs without /init
Update the "booting with initramfs" diagram.
Linux falls back to mounting the root device specified by root=
Tested on ARM on Linux 5.10
Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>
>---------------------------------------------------------------
b56c33f72de6bd12b3184135bbf06955951e6a1e
.../initramfs-boot-sequence.dia | 85 +++++++++++-----------
1 file changed, 43 insertions(+), 42 deletions(-)
diff --git a/slides/boot-sequence-initramfs/initramfs-boot-sequence.dia b/slides/boot-sequence-initramfs/initramfs-boot-sequence.dia
index bb08c7c9..634635a2 100644
--- a/slides/boot-sequence-initramfs/initramfs-boot-sequence.dia
+++ b/slides/boot-sequence-initramfs/initramfs-boot-sequence.dia
@@ -87,13 +87,13 @@
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@@ -154,7 +154,7 @@
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@@ -163,7 +163,7 @@
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@@ -183,13 +183,13 @@
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@@ -215,10 +215,10 @@
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@@ -232,7 +232,7 @@
<dia:real val="1.0583332926034927"/>
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<dia:color val="#000000ff"/>
@@ -248,10 +248,10 @@
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<dia:attribute name="obj_pos">
- <dia:point val="28.95,12.8"/>
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- <dia:rectangle val="28.0912,11.8399;29.8087,13.0515"/>
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@@ -265,7 +265,7 @@
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@@ -281,10 +281,10 @@
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@@ -303,7 +303,7 @@ Mounts the root filesystem and switches to it (switch_root)
<dia:real val="0.95249996334314346"/>
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@@ -422,14 +422,15 @@ Loads DTB + kernel to RAM, starts the kernel#</dia:string>
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<dia:attribute name="string">
<dia:string>#Initializes hardware devices and kernel subsystems
Extracts the initramfs archive to the file cache
-Starts the /init executable if found#</dia:string>
+Starts the /init executable if found
+(otherwise falls back to mounting the device specified by root=)#</dia:string>
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<dia:font family="Latin Modern Sans" style="0" name="Courier"/>
@@ -482,14 +483,14 @@ Starts the /init executable if found#</dia:string>
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@@ -510,13 +511,13 @@ Starts the /init executable if found#</dia:string>
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@@ -542,13 +543,13 @@ Starts the /init executable if found#</dia:string>
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@@ -574,10 +575,10 @@ Starts the /init executable if found#</dia:string>
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@@ -591,7 +592,7 @@ Starts the /init executable if found#</dia:string>
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@@ -607,10 +608,10 @@ Starts the /init executable if found#</dia:string>
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@@ -624,7 +625,7 @@ Starts the /init executable if found#</dia:string>
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@@ -640,10 +641,10 @@ Starts the /init executable if found#</dia:string>
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@@ -657,7 +658,7 @@ Starts the /init executable if found#</dia:string>
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@@ -673,14 +674,14 @@ Starts the /init executable if found#</dia:string>
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